Bromine Ion-Intercalated Layered BiWO as an Efficient Catalyst for Advanced Oxidation Processes in Tetracycline Pollutant Degradation Reaction.

The visible-light-driven photocatalytic degradation of pharmaceutical pollutants in aquatic environments is a promising strategy for addressing water pollution problems. This work highlights the use of bromine-ion-doped layered Aurivillius oxide, BiWO, to synergistically optimize the morphology and increase the formation of active sites on the photocatalyst's surface. The layered BiWO nanoplates were synthesized by a facile hydrothermal reaction in which bromine (Br) ions were introduced by adding cetyltrimethylammonium bromide (CTAB)/tetrabutylammonium bromide (TBAB)/potassium bromide (KBr). The as-synthesized BiWO nanoplates displayed higher photocatalytic tetracycline degradation activity (83.5%) than the BiWO microspheres (48.2%), which were obtained without the addition of Br precursors in the reaction medium. The presence of Br was verified experimentally, and the newly formed BiWO developed as nanoplates where the adsorbed Br ions restricted the multilayer stacking. Considering the significant morphology change, increased specific surface area, and enhanced photocatalytic performance, using a synthesis approach mediated by Br ions to design layered photocatalysts is expected to be a promising system for advancing water remediation.